1. Field of the Invention
This invention relates to a storage battery and more particularly refers to a new and improved storage battery, sealed gas- and liquid-tightly, with an electrode set enclosed in a casing, and method of producing it.
2. Description of the Prior Art
Alkaline storage batteries which are sealed gas- and liquid-tightly are known in varied designs. Popular among them are, in particular, circular cells, in which the electrode set is an electrode winding which is housed in a deep-drawn cup. The cup then forms one pole of the cell and it is sealed by a cover and a sealing- and insulating ring connected to the edge of the cup by a bead. The cover then forms the other pole of the cell. Joining the cover and the housing together in a gas- and liquid-tight manner presents special difficulties, as the alkaline electrolyte used penetrates even into the smallest gaps and crystallizes. This penetration is promoted by the overpressure in the cell, which is produced during charging and discharging.
Various procedures were tried in an effort to produce a seal which is as perfect as possible. Since bulging-out would frequently occur through pressing alone, resort was had to the expensive and time consuming step of calibrating the entire cell once more after the cover and the seal are beaded over. Unfortunately, because of the strong tendency of the alkaline electrolyte to leak, the recalibrated cells did not always achieve a perfect seal.